Can Electric Nose Breath Analysis Identify Abdominal Wall Hernia Recurrence and Aortic Aneurysms? A Proof-of-Concept Study

Abstract

Introduction. This pilot study evaluates if an electronic nose (eNose) can distinguish patients at risk for recurrent hernia formation and aortic aneurysm patients from healthy controls based on volatile organic compound analysis in exhaled air. Both hernia recurrence and aortic aneurysm are linked to impaired collagen metabolism. If patients at risk for hernia recurrence and aortic aneurysms can be identified in a reliable, low-cost, noninvasive manner, it would greatly enhance preventive options such as prophylactic mesh placement after abdominal surgery. Methods. From February to July 2017, a 3-armed proof-of-concept study was conducted at 3 hospitals including 3 groups of patients (recurrent ventral hernia, aortic aneurysm, and healthy controls). Patients were measured once at the outpatient clinic using an eNose with 3 metal-oxide sensors. A total of 64 patients (hernia, n = 29; aneurysm, n = 35) and 37 controls were included. Data were analyzed by an automated neural network, a type of self-learning software to distinguish patients from controls. Results. Receiver operating curves showed that the automated neural network was able to differentiate between recurrent hernia patients and controls (area under the curve 0.74, sensitivity 0.79, and specificity 0.65) as well as between aortic aneurysm patients and healthy controls (area under the curve 0.84, sensitivity 0.83, and specificity of 0.81). Conclusion. This pilot study shows that the eNose can distinguish patients at risk for recurrent hernia and aortic aneurysm formation from healthy controls.

Exhaled-Breath Testing Using an Electronic Nose during Spinal Cord Stimulation in Patients with Failed Back Surgery Syndrome: An Experimental Pilot Study

“…To further eliminate possible exogenous VOCs, the first two minutes of each 5 min measurement were only used to rinse the air in the lungs. The remaining three minutes were used in the analysis [21]. To familiarise patients with the device, patients could perform a few in-and exhales to get acquainted with the Aeonose™ before the actual measurements started.…”

“…Due to the lack of previous studies in this population, an exact sample size calculation for this pilot study was deemed unfeasible. For a standard proof-of-concept study with an electronic nose, 25 patients are required [21,34]. Therefore, in this pilot study we aimed to include at least 25 patients with FBSS who are treated with SCS.…”

“…Since exhaled breath contains hundreds of different VOCs, each individual has a unique volatile chemical breath print [21]. Electronic noses are composites of a sensor array and an in-built processor [22] whereby the sensor array gives a signal pattern after activation by an odour (i.e., they are not selective for individual molecules) [23].…”

Abdominal hernias and adhesions

“…In a recent published proof-of-concept study, it has been shown that patients with recurrent hernia could be distinguished from healthy controls using the eNose. 79 With the possibility to detect patients at risk to develop an incisional hernia, surgeons should be persuaded to use prophylactic meshes in these patients. Nowadays, surgeons are reluctant to use prophylactic meshes, in fear of mesh infections, while these meshes should often directly be placed after a gastrointestinal procedure.…”